The composites which contain silicon and natural graphite embedded in pyrolyzed carbon have been synthesized and investigated as anode material for lithium ion secondary batteries. Carbon coated onto silicon/graphite composites by using a pyrolysis reaction of phenolic resin at 1300℃. The pyrolyzed carbon was used as a buffer material and binder for silicon/graphite composites. As a result, the irreversibility and capacity decay were obviously improved with increasing amount of phenolic resin. A composite containing 45wt% phenolic resin, 45wt% graphite and 10wt% silicon exhibited a stable capacity of 443 mAh/g and better cycling performance.